A swollen neck may be caused by epidermoid cysts, lipomas and lymphadenitis. 1. Epidermoid cyst: Epidermoid cyst may be caused by skin damage, embryonic ectopic and other reasons that lead to the contents of the skin blocked in the skin, the disease can occur in all parts of the body surface, common symptoms include the appearance of the skin dome-shaped bulge of the swelling, normal skin color or light brown and so on. 2. Lipoma: the cause of the disease is still unclear, the tumor can occur in any part of the growth of fatty tissue, the patient’s local skin will appear one or more lumps, usually in the neck, shoulders, abdomen and other places. 3. Lymphadenitis: Lymphadenitis is mostly triggered by infection, which may be induced by cold and upper respiratory tract infection. The main symptom of the disease is pain and enlargement of the lymph nodes, and in severe cases, they will merge into larger lumps, which are commonly found in the neck and other places. There are many reasons for a swollen neck, so it is recommended that patients go to a regular hospital for examination to clarify the cause of the disease.